Translational spectroscopy of metastable fragments produced by dissociative excitation of atmospheric gases by electron impact: II. Carbon monoxide

Abstract

Oxygen atoms in the ${}_{}{}^5{}_{}{}^{}S_{}^o{}_{}{}^{}$ state and long-lived high-Rydberg states along with carbon atoms in long-lived high-Rydberg states produced by electron-impact dissociation of CO have been observed in a time-of-flight experiment. A number of dissociation limits were deduced and correlated with dissociation processes. Ranges of kinetic energies were established for the various fragments. The observed high-Rydberg features are discussed in terms of the ion-core model. The data are compared with other dissociative-excitation and analogous dissociative-ionization work. Correlation of observed features with molecular dissociative states was made where possible. The fact that dissociatively excited 1356-Å emissions are Doppler broadened and nonthermal in nature was deduced as a result of this work. This conclusion has import for radiative-transfer treatments of the upper atmospheres of Mars and Venus.